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class="meta-firstline"><span class="post-meta-date"><i class="far fa-calendar-alt fa-fw post-meta-icon"></i><span class="post-meta-label">发表于</span><time class="post-meta-date-created" datetime="2022-01-18T04:26:49.858Z" title="发表于 2022-01-18 12:26:49">2022-01-18</time><span class="post-meta-separator">|</span><i class="fas fa-history fa-fw post-meta-icon"></i><span class="post-meta-label">更新于</span><time class="post-meta-date-updated" datetime="2022-01-18T05:35:49.314Z" title="更新于 2022-01-18 13:35:49">2022-01-18</time></span><span class="post-meta-categories"><span class="post-meta-separator">|</span><i class="fas fa-inbox fa-fw post-meta-icon"></i><a class="post-meta-categories" href="/blog/categories/Shell/">Shell</a></span></div><div class="meta-secondline"><span class="post-meta-separator">|</span><span class="post-meta-wordcount"><i class="far fa-file-word fa-fw post-meta-icon"></i><span class="post-meta-label">字数总计:</span><span class="word-count">1.2k</span><span class="post-meta-separator">|</span><i class="far fa-clock fa-fw post-meta-icon"></i><span class="post-meta-label">阅读时长:</span><span>4分钟</span></span><span class="post-meta-separator">|</span><span class="post-meta-pv-cv" id="" data-flag-title="shell编程"><i class="far fa-eye fa-fw post-meta-icon"></i><span class="post-meta-label">阅读量:</span><span id="busuanzi_value_page_pv"></span></span></div></div></div></header><main class="layout" id="content-inner"><div id="post"><article class="post-content" id="article-container"><h5 id="1-运行-Shell-脚本有两种方法"><a href="#1-运行-Shell-脚本有两种方法" class="headerlink" title="1.运行 Shell 脚本有两种方法"></a>1.运行 Shell 脚本有两种方法</h5><h6 id="1-1-新建"><a href="#1-1-新建" class="headerlink" title="1.1  新建"></a>1.1  新建</h6><figure class="highlight shell"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br></pre></td><td class="code"><pre><span class="line"><span class="meta prompt_">#</span><span class="language-bash">!/bin/bash</span></span><br><span class="line">echo &quot;Hello World !&quot;</span><br></pre></td></tr></table></figure>

<h6 id="1-2-方式一"><a href="#1-2-方式一" class="headerlink" title="1.2 方式一"></a>1.2 方式一</h6><figure class="highlight shell"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br></pre></td><td class="code"><pre><span class="line"><span class="meta prompt_"># </span><span class="language-bash">1、作为可执行程序</span></span><br><span class="line">chmod +x ./test.sh  #使脚本具有执行权限</span><br><span class="line">./test.sh  #执行脚本</span><br><span class="line"><span class="meta prompt_"># </span><span class="language-bash">注意，一定要写成 ./test.sh，而不是 test.sh，运行其它二进制的程序也一样，直接写 test.sh，linux 系统会去 PATH 里寻找有没有叫 test.sh 的，而只有 /bin, /sbin, /usr/bin，/usr/sbin 等在 PATH 里，你的当前目录通常不在 PATH 里，所以写成 test.sh 是会找不到命令的，要用 ./test.sh 告诉系统说，就在当前目录找</span></span><br></pre></td></tr></table></figure>

<h6 id="1-3方式二"><a href="#1-3方式二" class="headerlink" title="1.3方式二"></a>1.3方式二</h6><figure class="highlight shell"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br></pre></td><td class="code"><pre><span class="line"><span class="meta prompt_"># </span><span class="language-bash">2、作为解释器参数</span></span><br><span class="line">sh test.sh</span><br></pre></td></tr></table></figure>

<hr>
<h5 id="2-变量"><a href="#2-变量" class="headerlink" title="2.变量"></a>2.变量</h5><h6 id="2-1变量规则"><a href="#2-1变量规则" class="headerlink" title="2.1变量规则"></a>2.1变量规则</h6><blockquote>
<figure class="highlight shell"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br></pre></td><td class="code"><pre><span class="line">your_name=&quot;runoob&quot;</span><br><span class="line"><span class="meta prompt_">#</span><span class="language-bash">变量名和等号之间不能有空格</span></span><br></pre></td></tr></table></figure>
</blockquote>
<h6 id="2-2-使用变量"><a href="#2-2-使用变量" class="headerlink" title="2.2 使用变量"></a>2.2 使用变量</h6><blockquote>
<p>使用一个定义过的变量，只要在变量名前面加美元符号即可</p>
<figure class="highlight shell"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br></pre></td><td class="code"><pre><span class="line">your_name=&quot;qinjx&quot;</span><br><span class="line">echo $your_name</span><br><span class="line">echo $&#123;your_name&#125;</span><br></pre></td></tr></table></figure>
</blockquote>
<h6 id="2-3只读变量"><a href="#2-3只读变量" class="headerlink" title="2.3只读变量"></a>2.3只读变量</h6><blockquote>
<p>使用 readonly 命令可以将变量定义为只读变量，只读变量的值不能被改变</p>
<figure class="highlight shell"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br></pre></td><td class="code"><pre><span class="line"><span class="meta prompt_">#</span><span class="language-bash">!/bin/bash</span></span><br><span class="line">myUrl=&quot;https://www.google.com&quot;</span><br><span class="line">readonly myUrl</span><br><span class="line">myUrl=&quot;https://www.runoob.com&quot;</span><br><span class="line"><span class="meta prompt_"></span></span><br><span class="line"><span class="meta prompt_">#</span><span class="language-bash">运行脚本，结果如下：</span></span><br><span class="line"><span class="meta prompt_">#</span><span class="language-bash">/bin/sh: NAME: This variable is <span class="built_in">read</span> only.</span></span><br></pre></td></tr></table></figure>
</blockquote>
<h5 id="2-4删除变量"><a href="#2-4删除变量" class="headerlink" title="2.4删除变量"></a>2.4删除变量</h5><blockquote>
<ul>
<li><p>使用 unset 命令可以删除变量</p>
</li>
<li><p>变量被删除后不能再次使用。unset 命令不能删除只读变量</p>
<figure class="highlight shell"><table><tr><td class="gutter"><pre><span class="line">1</span><br></pre></td><td class="code"><pre><span class="line">unset variable_name</span><br></pre></td></tr></table></figure></li>
</ul>
</blockquote>
<hr>
<h5 id="Shell-数组"><a href="#Shell-数组" class="headerlink" title="Shell 数组"></a>Shell 数组</h5><figure class="highlight shell"><table><tr><td class="gutter"><pre><span class="line">1</span><br></pre></td><td class="code"><pre><span class="line">数组名=(值1 值2 ... 值n)</span><br></pre></td></tr></table></figure>

<hr>
<h5 id="多行注释"><a href="#多行注释" class="headerlink" title="多行注释"></a>多行注释</h5><blockquote>
<figure class="highlight shell"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br></pre></td><td class="code"><pre><span class="line">:&lt;&lt;EOF</span><br><span class="line">注释内容...</span><br><span class="line">注释内容...</span><br><span class="line">注释内容...</span><br><span class="line">EOF</span><br></pre></td></tr></table></figure>
</blockquote>
<hr>
<h5 id="参数传递"><a href="#参数传递" class="headerlink" title="参数传递"></a>参数传递</h5><blockquote>
<ul>
<li>我们可以在执行 Shell 脚本时，向脚本传递参数，脚本内获取参数的格式为：**$n<strong>。</strong>n** 代表一个数字，1 为执行脚本的第一个参数，2 为执行脚本的第二个参数，以此类推……</li>
<li><strong>$0</strong> 为执行的文件名</li>
</ul>
</blockquote>
<hr>
<h5 id="Shell-基本运算符"><a href="#Shell-基本运算符" class="headerlink" title="Shell 基本运算符"></a>Shell 基本运算符</h5><blockquote>
<p>xpr 是一款表达式计算工具，使用它能完成表达式的求值操作</p>
</blockquote>
<figure class="highlight shell"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br></pre></td><td class="code"><pre><span class="line"><span class="meta prompt_">#</span><span class="language-bash">!/bin/bash</span></span><br><span class="line"></span><br><span class="line">val=`expr 2 + 2`</span><br><span class="line">echo &quot;两数之和为 : $val&quot;</span><br></pre></td></tr></table></figure>



<ul>
<li>运算符</li>
</ul>
<table>
<thead>
<tr>
<th>-eq</th>
<th>检测两个数是否相等，相等返回 true。</th>
<th>[ $a -eq $b ] 返回 false。</th>
</tr>
</thead>
<tbody><tr>
<td>-ne</td>
<td>检测两个数是否不相等，不相等返回 true。</td>
<td>[ $a -ne $b ] 返回 true。</td>
</tr>
<tr>
<td>-gt</td>
<td>检测左边的数是否大于右边的，如果是，则返回 true。</td>
<td>[ $a -gt $b ] 返回 false。</td>
</tr>
<tr>
<td>-lt</td>
<td>检测左边的数是否小于右边的，如果是，则返回 true。</td>
<td>[ $a -lt $b ] 返回 true。</td>
</tr>
<tr>
<td>-ge</td>
<td>检测左边的数是否大于等于右边的，如果是，则返回 true。</td>
<td>[ $a -ge $b ] 返回 false。</td>
</tr>
<tr>
<td>-le</td>
<td>检测左边的数是否小于等于右边的，如果是，则返回 true。</td>
<td>[ $a -le $b ] 返回 true。</td>
</tr>
</tbody></table>
<table>
<thead>
<tr>
<th>!</th>
<th>非运算，表达式为 true 则返回 false，否则返回 true。</th>
<th>[ ! false ] 返回 true。</th>
</tr>
</thead>
<tbody><tr>
<td>-o</td>
<td>或运算，有一个表达式为 true 则返回 true。</td>
<td>[ $a -lt 20 -o $b -gt 100 ] 返回 true。</td>
</tr>
<tr>
<td>-a</td>
<td>与运算，两个表达式都为 true 才返回 true。</td>
<td>[ $a -lt 20 -a $b -gt 100 ] 返回 false。</td>
</tr>
</tbody></table>
<table>
<thead>
<tr>
<th>&amp;&amp;</th>
<th>逻辑的 AND</th>
<th>[[ $a -lt 100 &amp;&amp; $b -gt 100 ]] 返回 false</th>
</tr>
</thead>
<tbody><tr>
<td>||</td>
<td>逻辑的 OR</td>
<td>[[ $a -lt 100 || $b -gt 100 ]] 返回 true</td>
</tr>
</tbody></table>
<ul>
<li>文件夹运算</li>
</ul>
<table>
<thead>
<tr>
<th>-b file</th>
<th>检测文件是否是块设备文件，如果是，则返回 true。</th>
<th>[ -b $file ] 返回 false。</th>
</tr>
</thead>
<tbody><tr>
<td>-c file</td>
<td>检测文件是否是字符设备文件，如果是，则返回 true。</td>
<td>[ -c $file ] 返回 false。</td>
</tr>
<tr>
<td>-d file</td>
<td>检测文件是否是目录，如果是，则返回 true。</td>
<td>[ -d $file ] 返回 false。</td>
</tr>
<tr>
<td>-f file</td>
<td>检测文件是否是普通文件（既不是目录，也不是设备文件），如果是，则返回 true。</td>
<td>[ -f $file ] 返回 true。</td>
</tr>
<tr>
<td>-g file</td>
<td>检测文件是否设置了 SGID 位，如果是，则返回 true。</td>
<td>[ -g $file ] 返回 false。</td>
</tr>
<tr>
<td>-k file</td>
<td>检测文件是否设置了粘着位(Sticky Bit)，如果是，则返回 true。</td>
<td>[ -k $file ] 返回 false。</td>
</tr>
<tr>
<td>-p file</td>
<td>检测文件是否是有名管道，如果是，则返回 true。</td>
<td>[ -p $file ] 返回 false。</td>
</tr>
<tr>
<td>-u file</td>
<td>检测文件是否设置了 SUID 位，如果是，则返回 true。</td>
<td>[ -u $file ] 返回 false。</td>
</tr>
<tr>
<td>-r file</td>
<td>检测文件是否可读，如果是，则返回 true。</td>
<td>[ -r $file ] 返回 true。</td>
</tr>
<tr>
<td>-w file</td>
<td>检测文件是否可写，如果是，则返回 true。</td>
<td>[ -w $file ] 返回 true。</td>
</tr>
<tr>
<td>-x file</td>
<td>检测文件是否可执行，如果是，则返回 true。</td>
<td>[ -x $file ] 返回 true。</td>
</tr>
<tr>
<td>-s file</td>
<td>检测文件是否为空（文件大小是否大于0），不为空返回 true。</td>
<td>[ -s $file ] 返回 true。</td>
</tr>
<tr>
<td>-e file</td>
<td>检测文件（包括目录）是否存在，如果是，则返回 true。</td>
<td>[ -e $file ] 返回 true。</td>
</tr>
</tbody></table>
<ul>
<li>字符串运算：</li>
</ul>
<table>
<thead>
<tr>
<th align="left">运算符</th>
<th align="left">说明</th>
<th align="left">举例</th>
</tr>
</thead>
<tbody><tr>
<td align="left">&#x3D;</td>
<td align="left">检测两个字符串是否相等，相等返回 true。</td>
<td align="left">[ $a &#x3D; $b ] 返回 false。</td>
</tr>
<tr>
<td align="left">!&#x3D;</td>
<td align="left">检测两个字符串是否不相等，不相等返回 true。</td>
<td align="left">[ $a !&#x3D; $b ] 返回 true。</td>
</tr>
<tr>
<td align="left">-z</td>
<td align="left">检测字符串长度是否为0，为0返回 true。</td>
<td align="left">[ -z $a ] 返回 false。</td>
</tr>
<tr>
<td align="left">-n</td>
<td align="left">检测字符串长度是否不为 0，不为 0 返回 true。</td>
<td align="left">[ -n “$a” ] 返回 true。</td>
</tr>
<tr>
<td align="left">$</td>
<td align="left">检测字符串是否为空，不为空返回 true。</td>
<td align="left">[ $a ] 返回 true。</td>
</tr>
</tbody></table>
</article><div class="post-copyright"><div class="post-copyright__author"><span class="post-copyright-meta">文章作者: </span><span class="post-copyright-info"><a href="mailto:undefined">Albert Yuan</a></span></div><div class="post-copyright__type"><span class="post-copyright-meta">文章链接: </span><span class="post-copyright-info"><a href="https://yllove.gitee.io/2022/01/18/shell%E7%BC%96%E7%A8%8B/shell%E7%BC%96%E7%A8%8B/">https://yllove.gitee.io/2022/01/18/shell%E7%BC%96%E7%A8%8B/shell%E7%BC%96%E7%A8%8B/</a></span></div><div class="post-copyright__notice"><span class="post-copyright-meta">版权声明: </span><span class="post-copyright-info">本博客所有文章除特别声明外，均采用 <a href="https://creativecommons.org/licenses/by-nc-sa/4.0/" target="_blank">CC BY-NC-SA 4.0</a> 许可协议。转载请注明来自 <a href="https://yllove.gitee.io" target="_blank">Albert Yuan's Blog</a>！</span></div></div><div class="tag_share"><div class="post-meta__tag-list"><a class="post-meta__tags" href="/blog/tags/shell/">shell</a></div><div 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card-announcement-animation"></i><span>公告</span></div><div class="announcement_content">love cat , love life</div></div><div class="sticky_layout"><div class="card-widget" id="card-toc"><div class="item-headline"><i class="fas fa-stream"></i><span>目录</span></div><div class="toc-content"><ol class="toc"><li class="toc-item toc-level-5"><a class="toc-link" href="#1-%E8%BF%90%E8%A1%8C-Shell-%E8%84%9A%E6%9C%AC%E6%9C%89%E4%B8%A4%E7%A7%8D%E6%96%B9%E6%B3%95"><span class="toc-text">1.运行 Shell 脚本有两种方法</span></a><ol class="toc-child"><li class="toc-item toc-level-6"><a class="toc-link" href="#1-1-%E6%96%B0%E5%BB%BA"><span class="toc-text">1.1  新建</span></a></li><li class="toc-item toc-level-6"><a class="toc-link" href="#1-2-%E6%96%B9%E5%BC%8F%E4%B8%80"><span class="toc-text">1.2 方式一</span></a></li><li class="toc-item toc-level-6"><a class="toc-link" href="#1-3%E6%96%B9%E5%BC%8F%E4%BA%8C"><span class="toc-text">1.3方式二</span></a></li></ol></li><li class="toc-item toc-level-5"><a class="toc-link" href="#2-%E5%8F%98%E9%87%8F"><span class="toc-text">2.变量</span></a><ol class="toc-child"><li class="toc-item toc-level-6"><a class="toc-link" href="#2-1%E5%8F%98%E9%87%8F%E8%A7%84%E5%88%99"><span class="toc-text">2.1变量规则</span></a></li><li class="toc-item toc-level-6"><a class="toc-link" href="#2-2-%E4%BD%BF%E7%94%A8%E5%8F%98%E9%87%8F"><span class="toc-text">2.2 使用变量</span></a></li><li class="toc-item toc-level-6"><a class="toc-link" href="#2-3%E5%8F%AA%E8%AF%BB%E5%8F%98%E9%87%8F"><span class="toc-text">2.3只读变量</span></a></li></ol></li><li class="toc-item toc-level-5"><a class="toc-link" href="#2-4%E5%88%A0%E9%99%A4%E5%8F%98%E9%87%8F"><span class="toc-text">2.4删除变量</span></a></li><li class="toc-item toc-level-5"><a class="toc-link" href="#Shell-%E6%95%B0%E7%BB%84"><span class="toc-text">Shell 数组</span></a></li><li class="toc-item toc-level-5"><a class="toc-link" href="#%E5%A4%9A%E8%A1%8C%E6%B3%A8%E9%87%8A"><span class="toc-text">多行注释</span></a></li><li class="toc-item toc-level-5"><a class="toc-link" href="#%E5%8F%82%E6%95%B0%E4%BC%A0%E9%80%92"><span class="toc-text">参数传递</span></a></li><li class="toc-item toc-level-5"><a class="toc-link" href="#Shell-%E5%9F%BA%E6%9C%AC%E8%BF%90%E7%AE%97%E7%AC%A6"><span class="toc-text">Shell 基本运算符</span></a></li></ol></div></div><div class="card-widget card-recent-post"><div class="item-headline"><i class="fas fa-history"></i><span>最新文章</span></div><div class="aside-list"><div class="aside-list-item"><a class="thumbnail" href="/blog/2023/02/07/iOS%E5%BC%80%E5%8F%91%E8%BF%9B%E9%98%B6/iOS-%E8%87%AA%E5%AE%9A%E4%B9%89%E7%BD%91%E9%A1%B5%E4%B8%8B%E8%BD%BDIPA%E5%8C%85/" title="iOS 自定义网页下载IPA包"><img src= "" data-lazy-src="https://img.mp.itc.cn/upload/20170409/1a8f793d7282451cbd1beb6841608c90_th.jpeg" onerror="this.onerror=null;this.src='/blog/img/defaultCover.gif'" alt="iOS 自定义网页下载IPA包"/></a><div class="content"><a class="title" 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